Question: Which aspects of the explosion characteristics of coal dust were investigated by the quantitative explosibility studies at CSIR-CBRI in Roorkee, India, in the process of designing safety measures for coal dust handling?
Paraphrase: Which aspects of the explosion characteristics of coal dust were investigated by the quantitative explosibility studies at CSIR-CBRI in Roorkee, India, in the process of designing safety measures for coal dust handling?
SPARQL (Wikidata): select ?ent where { ?ent wdt:P31 wd:Q416796 . ?ent wdt:P2204 ?obj } ORDER BY DESC(?obj)LIMIT 5 
Answer: starch